England international James Milner scored a fifth-minute penalty to give Liverpool a 1-0 lead on the night and on aggregate after a stalemate in the first leg in Germany.
The Reds were unable to double their advantage despite Philippe Coutinho, Jordan Henderson and Daniel Sturridge all having decent chances at Anfield.
Jurgen Klopp’s side managed to hold on despite a nervy finish to book their place in Friday’s Europa League last-16 draw.
And Sakho posed for a dressing room selfie with Can and Firmino following their latest European triumph.
Sakho wrote: “Thank you for your support tonight 👏🏿 #YNWA #LiverpoolFC #LFC”
Liverpool face Manchester City in the League Cup final at Wembley on Sunday afternoon.
The Reds are in eighth place and nine points behind Manchester City in the Premier League table in the race to secure a spot in next season’s Champions League.
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